Although most environmental signals are analog signals, digital signal processing (hereinafter, DSP) has many advantages such as, more precise and more flexible, and DSP design has become the mainstream of electronics systems. Therefore, in many electronics applications, analog signals are converted into digital signals, and the analog-to-digital converters (hereinafter, ADC) are essential components nowadays.
The precision of a DSP system, especially a communication system, is dominated by the resolution of its digital input signal and precision of ADC is important. Delta-sigma (hereinafter, ΔΣ) ADCs have become more and more popular in high-resolution ADCs due to its characteristics such as high resolution, high stability, low power and low cost.
A ΔΣ-modulator is the most important component in the ΔΣ-ADC and a quantization process performed in the ΔΣ-modulator introduces a quantization error. The quantization error is an inherent but undesirable factor of the ΔΣ-ADC. Therefore, suppressing side effects caused by the quantization error is especially attractive for high speed applications.